The project is designed to control the speed of a DC motor using an ARM series processor. The speed of DC motor is directly proportional to the voltage applied across its terminals. Hence, if voltage across motor terminal is varied, then speed can also be varied.

This project uses the above principle to control the speed of the motor by varying the duty cycle of the pulse applied to it (popularly known as PWM control). The project uses input button interfaced to the processor, which are used to control the speed of motor. PWM (Pulse Width Modulation) is generated at the output by the microcontroller as per the program. The program is written in Embedded C.

The average voltage given or the average current flowing through the motor will change depending on the duty cycle (ON and OFF time of the pulses), so the speed of the motor will change. A motor driver IC is interfaced to the STM32 board for receiving PWM signals and delivering desired output for speed control of a small DC motor.

Further the project can be enhanced by using power electronic devices such as IGBTs to achieve speed control higher capacity industrial motors.

A: There is some approximated formula .Peak to peak ripple voltage = Load current in amps / (2*line frequency in hertz *capacitance in farads). But as rule of thumb for 1 A current 1000uF is best. Thus it is load dependent.

Q: What is the family of microcontroller is used?

A: ARM7 cortex (STM32) processor is used and development board is also provided with this project.

Yes the kit delivered to me on right time with the right components.Initially I have a doubt but it is cleared by your team. The technical support is good.The Soldering kit should be good enough.I recommended to my college juniors.